1. Field of the Invention
This invention relates to fire sprinkler systems used in commercial or residential buildings and, more particularly, to an improved sprinkler head adaptor.
2. Description of the Related Art
In all sorts of commercial or residential buildings and structures, fire sprinkler systems are designed and installed to provide a degree of safety and protection to the occupants as well as to the building and its contents in the event of a fire. In certain applications, fire sprinkler systems are also required to be installed by law or other building codes or regulations.
Typically, a fire sprinkler system includes a series of interconnected pipes that are placed overhead in the ceiling where the pipes are connected to a source of water and the water can flow through the pipes when the system is tripped in the event of a fire. The water source can come from water that is provided to the building from the city's main water pipes. A series of sprinkler heads connected to the pipe system and strategically placed throughout the ceiling area of the building allow water to spray out in the event of fire. In this manner, when fire occurs and the fire sprinkler system is activated, water is sprayed from the sprinkler heads in the ceiling areas and onto the occupants and other contents of the building so as to extinguish the fire or to contain or slow down the spread of fire until additional help can be provided by fire fighting units.
Currently, in typical fire sprinkler system installations, the interconnected pipes that carry the water to sprinkler heads are made of suitable fire-safe material, such as CPVC (Chlorinated polyvinyl chloride), that has been approved by applicable building and inspection codes. For the most part, these interconnected pipes are placed in a horizontal plane in the ceiling area, and in certain parts of the building they may need to run in other directions to navigate the building as appropriate. Wherever a sprinkler head is needed, a T-shaped connector that is typically made of the same CPVC material as the main pipes is fitted and connected on two of its in-line ends onto the main pipe by use of liquid glue there between to form a leak-proof connection. The third branch of the T-connector that is usually perpendicular to the two in-line branches is positioned so that it's opening faces downward.
Specifically, in existing systems, the sprinkler head usually needs to be positioned several inches or more below the level of the main pipe system in the ceiling, and for that purpose a separate piece of pipe extension is first connected to the third branch of the T-connector that is facing down, and then the sprinkler head is connected to that pipe extension. More specifically, the pipe extension is connected to the T-connector by applying suitable liquid glue around the upper end and rim of the pipe extension and inside the T-connector so that the two joined pieces form a solid and permanent leak-proof connection. At the lower end of the pipe extension, a CPVC sprinkler head adaptor is then fitted over and connected to the lower end of the pipe extension by applying glue between the upper end or rim of the adaptor and the lower end or rim of the pipe extension. The lower end of the sprinkler head adaptor is provided with female threads. The female threaded end of the sprinkler head adaptor can be injection molded as part of the same CPVC plastic material that is used for the remainder of the adaptor. Alternatively, in existing designs, a brass nut with female threads is placed at the lower end of the CPVC sprinkler head adaptor during the injection molding process of the adaptor. Regardless of whether the lower female threaded end of the head adaptor is made of CPVC material or is made of a brass nut, a fire sprinkler head that has a male threaded brass connector at its end opposite the sprinkler end is threaded inside the female threaded connector of the CPVC adaptor.
These existing systems of installation have certain disadvantages and drawbacks. For example, whenever the brass male threads of a sprinkler head are threaded inside the plastic injection molded female threads of a connector or adapter, the plastic female threads are susceptible to cracking and breakage due to the pressure created by the brass male threads of the sprinkler head.
In addition, in situations where the pipe extension is used to install the sprinkler head some distance below the horizontal plane of the main water carrying pipes, several problems are encountered. For example, because liquid glue is used to connect the lower end of the pipe extension to the plastic sprinkler head adaptor, often times the liquid glue oozes or seeps out of the connection, which is messy. The liquid glue can also run inside the head adaptor, which may block or restrict the flow of water to the sprinkler head. Another problem is that the installation of a plastic sprinkler head adaptor by gluing it to the lower end of the pipe extension takes too much time, material, and labor.
In view of the foregoing, a fire sprinkler extension and head adaptor design is needed that is less expensive, requires less time to install, and provides for a more secure connection between the various pieces. The present invention fulfills these and other needs.